Lights Off: Our Gadgets Have Way Too Many LEDs

Where has all the darkness gone? Appliances, toys, and gadgets fill our nighttime hours with an ever-present glow. In this edition of "Don't Ask Glenn," PM Tech Editor Glenn Derene says it's time to turn off the extraneous illumination.

When I was a child, in the 1970s, my parents plugged in a 4-watt night light near my bedroom door to keep me from crashing into walls on my way to the bathroom. My two young sons don't need such a thing. Their rooms are lit by the soft glow of LEDs, seeping out of various appliances, toys, and electronic devices. Together they produce what I call the underglow. It has infiltrated every corner of my home, which I can navigate at night by LED beacons alone.

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LED indicators are suffering from gratuitous overuse. Commercial light-emitting diodes were first used in Hewlett-Packard calculators in the 1960s, and in the '70s Fairchild Optoelectronics introduced a planar process that reduced the cost to pennies apiece. Today, the lights are everywhere, silently communicating: "Your phone is charging." "Your hard drive is working." "Your baby monitor is monitoring."

Alan Hedge, a professor of ergonomics at Cornell University's Department of Design and Environmental Analysis, says the lights should convey three types of "need to know" information: power (the device is on), warning (something's wrong), or confirmation of action (something's changed). All else is decorative or extraneous. "Good ergonomic design means you provide the appropriate amount of information," he says.

In most cases, an indicator light simply lets you know the device is on. But most modern electronics are in a constant state of standby, so the LED glows whether or not a device is in use. Some gadgets blink while standing by; in sleep mode, Apple's MacBook Pro pulses its light like a synesthetic snorer.

The LED indicator proliferation is due partly to the litigious nature of consumer culture. (Hedge cites manufacturers' fears of "failure to warn" lawsuits.) But most LEDs are added because product designers see no reason not to. "Often in the world of design, if you can afford to do something, you do it," Hedge says. But even if a functional case could be made for each of these lights individually, in aggregate they just create sensory pollution and dilute the message each light ought to deliver: "Hey, something's going on with this device."

I'm a lover of electronics—but also a canary in this particular coal mine. If the glowing lights in my house indicate a trend, then I'd like to start the backlash now. Enough with the LEDs already. If there's no critical reason for a device to emit light, then it shouldn't emit light. We consumers are not afraid of the dark.